2024年4月7日发(作者：止婉)

1 of 19 July 18, 2008 INSERTS A to L, CHAPTER 50_JAPAN_7-18-08

INSERT A: (Page # 241 of ‘as published in the 2

nd

edition’)

The purpose of this chapter is to comment on the development of Japanese codes and standards on

boilers, pressure vessels and piping items for chemical, petroleum, thermal and nuclear power industries.

In addition, included is a relation between government laws and voluntary consensus codes. This Chapter

revision is based on Second Edition (2006) written by late Yasuhide Asada, late Toshiki Karasawa and

Yoshinori Kajimura.

INSERT B: (Page # 248 of ‘as published in the 2

nd

edition’)

Copy Editor

Use Figures from pages 15-17 of the Word File ‘Chapter 50 Rev_ 4_Red font for changes_7-

17-08’. Locate these Figures as noted in the text.

50.3.2 High Pressure Institute Code (HPIS)

50.3.2.1 Overview of HPIS Z 101

The High Pressure Institute (HPI) of Japan had developed a fitness-for-service code HPIS Z 101,

Assessment Procedure for Crack-like Flaws in Pressure Equipment [1, 2, 3]. This Code is applicable to

pressure vessels, piping items, storage tanks, etc. for general industrial facilities. HPIS Z 101 comprises

applicability of pressurized equipment and requirement of data for evaluation, assessment procedure of

acceptable criteria and treatment based on evaluation. This Code is applicable to flaws in the pressurized

cylinders with R/t ≥ 5, where R is the inner radius and t is the wall thickness of the cylinder. Creep

cracking is out of scope in this Code. First edition of HPI S Z 101 was published in 2001 and a revised

edition is to be published in 2008.

50.3.2.2 Organization

Subcommittee of Fitness-for-Service for Pressure Equipment established by Pressure Vessel Code

Committee had issued HPIS Z 101 Code, through deliberations by the Standardization Committee and

Executive Board in The High Pressure Institute of Japan.

50.3.2.3 Structures

General structure of the HPI S Z 101 consists of two steps, step I and step II. The step I is the

determination of allowable flaws in accordance with acceptance standard procedure, using minimum

allowable metal temperature (MAT). Step II is the assessment of flaws not satisfying step I. Currently,

the step II is for future action.

2 of 19 July 18, 2008 INSERTS A to L, CHAPTER 50_JAPAN_7-18-08

(1) Outline of Flaw Evaluation Procedure

Flaw assessment diagram is illustrated in Fig. 50. 1. The sequence of the assessment in step I is the

initial decision whether a flaw should be removed or not, after its detection by non-destructive

examination (NDE). If the flaw is removed from the component, strength evaluation shall be

requested for stress analyses in the metal loss thin areas. If the flaw is not removed, indication

detected at inspection is sized by the bounding rectangle or square and actual flaw is modeled as an

elliptical flaw or a semi-elliptical flaw to determine depth and length. If multiple flaws are detected,

aligned and combination rules are applied, which are the same with the ASME BPVC Section XI

(2001).

If the detected flaw is around the area of the structural discontinuity region, the flaw is assessed by

step II, because the stress distribution is complex. In addition, if the detected flaw is located in the

component with the thickness greater than 150 mm, the flaw is also assessed by step II, because

required fracture toughness is different beyond 150 mm. It is not eligible to use step II for the flaw in

stress concentration area and wall thickness greater than 150 mm.

If the flaw is located out of welded zone and impact test data for the material are not available, the

minimum allowable temperature (MAT) shown in Figure 50. 2 shall be determined from the impact

test exemption curve defined by the Code. If the

flaw is located in welded zone and impact test

data are estimated appropriately, MAT shall be

determined from the required absorbed energy

given by the Code.

Confirmation is required that the operating

temperature of the component shall be higher

than that maximum MAT, and the size of the

flaw modeled from the indication shall be

within the Acceptance Standard, as shown in

Fig. 50.3. Furthermore, the flaw within the

Acceptance Standard is requested to have no

possibility to grow during the future evaluation

period. When these conditions are satisfied, the

flaw becomes allowable and continuing

operation is feasible providing fatigue life

evaluation in case of cyclic operation.

In case the flaw meets the Acceptance

Standard, and the flaw has a possibility to grow

during the operation, estimation of flaw growth

amount is requested. If the flaw size taking into

account the amount of the flaw growth is less

than the Acceptance Standard, the flaw is acceptable.

FIG. 50. 1 FLAW ASSESSMENT

DIAGRAM IN HPI S Z 101.

2024年4月7日发(作者：止婉)

1 of 19 July 18, 2008 INSERTS A to L, CHAPTER 50_JAPAN_7-18-08

INSERT A: (Page # 241 of ‘as published in the 2

nd

edition’)

The purpose of this chapter is to comment on the development of Japanese codes and standards on

boilers, pressure vessels and piping items for chemical, petroleum, thermal and nuclear power industries.

In addition, included is a relation between government laws and voluntary consensus codes. This Chapter

revision is based on Second Edition (2006) written by late Yasuhide Asada, late Toshiki Karasawa and

Yoshinori Kajimura.

INSERT B: (Page # 248 of ‘as published in the 2

nd

edition’)

Copy Editor

Use Figures from pages 15-17 of the Word File ‘Chapter 50 Rev_ 4_Red font for changes_7-

17-08’. Locate these Figures as noted in the text.

50.3.2 High Pressure Institute Code (HPIS)

50.3.2.1 Overview of HPIS Z 101

The High Pressure Institute (HPI) of Japan had developed a fitness-for-service code HPIS Z 101,

Assessment Procedure for Crack-like Flaws in Pressure Equipment [1, 2, 3]. This Code is applicable to

pressure vessels, piping items, storage tanks, etc. for general industrial facilities. HPIS Z 101 comprises

applicability of pressurized equipment and requirement of data for evaluation, assessment procedure of

acceptable criteria and treatment based on evaluation. This Code is applicable to flaws in the pressurized

cylinders with R/t ≥ 5, where R is the inner radius and t is the wall thickness of the cylinder. Creep

cracking is out of scope in this Code. First edition of HPI S Z 101 was published in 2001 and a revised

edition is to be published in 2008.

50.3.2.2 Organization

Subcommittee of Fitness-for-Service for Pressure Equipment established by Pressure Vessel Code

Committee had issued HPIS Z 101 Code, through deliberations by the Standardization Committee and

Executive Board in The High Pressure Institute of Japan.

50.3.2.3 Structures

General structure of the HPI S Z 101 consists of two steps, step I and step II. The step I is the

determination of allowable flaws in accordance with acceptance standard procedure, using minimum

allowable metal temperature (MAT). Step II is the assessment of flaws not satisfying step I. Currently,

the step II is for future action.

2 of 19 July 18, 2008 INSERTS A to L, CHAPTER 50_JAPAN_7-18-08

(1) Outline of Flaw Evaluation Procedure

Flaw assessment diagram is illustrated in Fig. 50. 1. The sequence of the assessment in step I is the

initial decision whether a flaw should be removed or not, after its detection by non-destructive

examination (NDE). If the flaw is removed from the component, strength evaluation shall be

requested for stress analyses in the metal loss thin areas. If the flaw is not removed, indication

detected at inspection is sized by the bounding rectangle or square and actual flaw is modeled as an

elliptical flaw or a semi-elliptical flaw to determine depth and length. If multiple flaws are detected,

aligned and combination rules are applied, which are the same with the ASME BPVC Section XI

(2001).

If the detected flaw is around the area of the structural discontinuity region, the flaw is assessed by

step II, because the stress distribution is complex. In addition, if the detected flaw is located in the

component with the thickness greater than 150 mm, the flaw is also assessed by step II, because

required fracture toughness is different beyond 150 mm. It is not eligible to use step II for the flaw in

stress concentration area and wall thickness greater than 150 mm.

If the flaw is located out of welded zone and impact test data for the material are not available, the

minimum allowable temperature (MAT) shown in Figure 50. 2 shall be determined from the impact

test exemption curve defined by the Code. If the

flaw is located in welded zone and impact test

data are estimated appropriately, MAT shall be

determined from the required absorbed energy

given by the Code.

Confirmation is required that the operating

temperature of the component shall be higher

than that maximum MAT, and the size of the

flaw modeled from the indication shall be

within the Acceptance Standard, as shown in

Fig. 50.3. Furthermore, the flaw within the

Acceptance Standard is requested to have no

possibility to grow during the future evaluation

period. When these conditions are satisfied, the

flaw becomes allowable and continuing

operation is feasible providing fatigue life

evaluation in case of cyclic operation.

In case the flaw meets the Acceptance

Standard, and the flaw has a possibility to grow

during the operation, estimation of flaw growth

amount is requested. If the flaw size taking into

account the amount of the flaw growth is less

than the Acceptance Standard, the flaw is acceptable.

FIG. 50. 1 FLAW ASSESSMENT

DIAGRAM IN HPI S Z 101.